Feasibility of simplifying renal dosimetry in ¹⁷⁷Lu peptide receptor radionuclide therapy

TY - JOUR

T1 - Feasibility of simplifying renal dosimetry in 177Lu peptide receptor radionuclide therapy

AU - Sundlöv, Anna

AU - Gustafsson, Johan

AU - Brolin, Gustav

AU - Mortensen, Nadja

AU - Hermann, Rebecca

AU - Bernhardt, Peter

AU - Svensson, Johanna

AU - Ljungberg, Michael

AU - Tennvall, Jan

AU - Sjögreen Gleisner, Katarina

PY - 2018/12/1

Y1 - 2018/12/1

N2 - Background: Recently, 177Lu-dotatate therapy for neuroendocrine tumours has received regulatory approval. Dosimetry can be used to optimize treatment on an individual basis, but there is no international consensus as to how it should be done. The aim of this study is to determine a feasible and accurate dosimetry method to guide individualized peptide receptor radionuclide therapy (PRRT) for patients with neuroendocrine tumours. As part of a clinical trial on 177Lu-dotatate therapy, renal dosimetry was performed for all patients in each treatment cycle, using a hybrid planar-SPECT/CT method. In the present study, we use the image data acquired from 22 patients and 119 cycles and define a set of alternative treatment planning strategies, each representing a simplification in terms of image acquisition and dosimetric calculations. The results from the simplified strategies are compared to the results from the protocol-prescribed hybrid planar-SPECT/CT-based method by analysing differences both in per-cycle and total cumulative absorbed dose (AD) analyses. Results: In general, the SPECT-based methods gave results that were largely consistent with the protocol-specified hybrid method, both in the per-cycle and cumulative AD analyses. Notably, performing one SPECT/CT per cycle at 96 h yielded ADs that were very similar to the protocol method. The methods using planar dosimetry resulted in larger variations, as expected, while giving 4 cycles to all patients resulted in the largest inter-individual differences in cumulative AD. Conclusions: Performing one SPECT/CT at 96 h in every treatment cycle gives sufficiently reliable dosimetric results to base individualized treatment planning on, with a reasonable demand on resources.

AB - Background: Recently, 177Lu-dotatate therapy for neuroendocrine tumours has received regulatory approval. Dosimetry can be used to optimize treatment on an individual basis, but there is no international consensus as to how it should be done. The aim of this study is to determine a feasible and accurate dosimetry method to guide individualized peptide receptor radionuclide therapy (PRRT) for patients with neuroendocrine tumours. As part of a clinical trial on 177Lu-dotatate therapy, renal dosimetry was performed for all patients in each treatment cycle, using a hybrid planar-SPECT/CT method. In the present study, we use the image data acquired from 22 patients and 119 cycles and define a set of alternative treatment planning strategies, each representing a simplification in terms of image acquisition and dosimetric calculations. The results from the simplified strategies are compared to the results from the protocol-prescribed hybrid planar-SPECT/CT-based method by analysing differences both in per-cycle and total cumulative absorbed dose (AD) analyses. Results: In general, the SPECT-based methods gave results that were largely consistent with the protocol-specified hybrid method, both in the per-cycle and cumulative AD analyses. Notably, performing one SPECT/CT per cycle at 96 h yielded ADs that were very similar to the protocol method. The methods using planar dosimetry resulted in larger variations, as expected, while giving 4 cycles to all patients resulted in the largest inter-individual differences in cumulative AD. Conclusions: Performing one SPECT/CT at 96 h in every treatment cycle gives sufficiently reliable dosimetric results to base individualized treatment planning on, with a reasonable demand on resources.

KW - 177-Lutetium

KW - Dosimetry

KW - Dotatate

KW - Neuroendocrine

KW - PRRT

KW - SPECT

U2 - 10.1186/s40658-018-0210-2

DO - 10.1186/s40658-018-0210-2

M3 - Article

C2 - 29974391

AN - SCOPUS:85049693337

VL - 5

JO - EJNMMI Physics

JF - EJNMMI Physics

SN - 2197-7364

IS - 1

M1 - 12

ER -